Foreign minister says if measures fail to stem migrant flow Mexico will consider implementing a regional framework for asylum seekers.

As part of a deal to avert tariffs, Mexico agreed to revisit U.S. demands for a radical overhaul of the immigration system if its proposed measures to curb migration don’t work, putting it under intense pressure to stem the tide of Central Americans arriving at the U.S. border. President Trump on Monday wrote on Twitter that the two countries had “fully signed and documented another very important part of the Immigration and Security deal with Mexico” that would require a vote by Mexican lawmakers. That was an apparent reference to a “safe third country” designation that would require migrants fleeing their homelands who pass through Mexico to seek asylum there. “We do not anticipate a problem with the vote but, if for any reason the approval is not forthcoming, Tariffs will be reinstated!” Mr. Trump added. But Mexican Foreign Minister Marcelo Ebrard said that no additional agreements had been finalized beyond Friday’s pact, which he said delayed for now the Trump administration’s demands for Mexico to become a safe third country.

Mexico believes that an overhauled asylum system must include the participation of the U.N. Refugee Agency and other Central American governments to share the responsibility of receiving asylum seekers, Mr. Ebrard said.

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